Headgear structure



March 27, 1956 p FR|EDER ET'AL 2,739,309

HEADGEAR STRUCTURE 7 Sheets-Sheet 1 Filed Dec. 21, 1950 INVENTORS. LEONARD P. FRIE DER BY WALTER s. FINKEN MJM ATTORNEY.

March 27, 1956 p. FRlEDER ETAL 2,739,309

HEADGEAR STRUCTURE Filed Dec. 21, 1950 7 Sheets-Sheet 2 FIG. 2 86 84 36 FIG. 3

INVENTORS. LEONARD P. FRIEDER WALTER S. FINKEN 27 y ATTORNEY.

March 27, 1956 p D R ETAL 2,739,309

HEADGEAR STRUCTURE 7 Sheets-Sheet 5 Filed Dec. 21, 1950 INVENTORS. LEONARD P. FRIEDER WALTER 5. FINKEN Aw Z 44 ATTORNEY.

March 27, 1956 Filed Dec. 21, 1950 L. P. FRIEDER ETAL HEADGEAR STRUCTURE 7 Sheets-Sheet 4 ATTORNEY.

March 27, 1956 L. P. FRIEDER ETAL 2,739,309

HEADGEAR STRUCTURE 7 Sheets-Sheet 5 Filed Dec. 21, 1950 R am ME mm E VP m0 R A N O E L WALTER S. FINKEN BY May/14% ATTORNEY.

March 27, 1956 L. P. FRIEDER ETAL HEADGEAR STRUCTURE 7 Sheets-Sheet 6 Filed Dec. 21, 1950 INVENTORS. LEONARD P. FRIEDER WALTER S. FINKEN ATTORNEY.

March 1956 1.. P. FRIEDER ETAL 2,739,309

HEADGEAR STRUCTURE 7 Sheets-Sheet 7 Filed Dec. 21, 1950 FIG. i4

ATTQRNEY.

aseous HEADGEAR srnucrunn Application December 21, 1959, Serial No. $71,904

This invention relates to protective helmets and particularly to helmets designed for protecting the head of the wearer against heavy blows and against impact of objects which might tend to crack and penetrate a helmet of inferior strength.

Although devices of the character herein disclosed may be used for a wide variety of purposes, andwith helmets having shells of various materials, a particularlyimportant application of the invention is in helmets designed for aviators and the like, where the circumstances of the wearer may subject him to severe blows about the head. For example, in high speed aircraft rapid turns, dives and other usual or unusual operations often throw the pilot or passenger against adjacent structural parts or the aircraft, with considerable force; in consequence a protective helmet is practically a necessity for personncl under such conditions, to protect the skull from injury. Since the helmet must often be worn for long periods of time, it should be as light in weight and as comfortable as possible. indeed lightness of weight is a particularly im ortant feature, since the same accelerations and decelations which tend to throw the wearers head about will likewise tend to displace a heavy helmet relative to his head, putting extra pressures on his head in an uncomfortable and tiring manner even without impact of external objects.

One common structure of helmet involves a relatively rigid shell with rubber cushions or the like interposed between the shell and the persons head; but in such case, a blow on the shell compresses the rubber cushion and brings the shell close to the head. Even though this arrangement may in many cases somewhat insulate the head from the original impact, a blow which deforms or even partly pierces the shell may cause serious injury. In some other type of helmets, a rather tight fitting headband is secured to the inner face ofthe shell, at such r a position that the top of the helmet normally floats at a spaced distance above the head, but in such cases, a blow even on the upper part of the shell may drive the latter against the head, by forcing the headband down.

A primary object of the present invention is to provide an improved protective helmet, embodying a shell structure which is itself much more able to withstand shattering or penetration under impact, together with a novel mounting and head-engaging structure that positively maintains the shell at a spaced distance from the head, in essentially all directions, even under heavy impact at any locality of the shell.

A further and more specific object is to provide a protective helmet having a head-mounting arrangement which is light in weight, comfortable, and yet extremely effective to hold the helmet shell at a safe distance from the wearers head, in all directions, maintaining such spacing by means which positively engage the head and cause to follow, if necessary, any actual motion of the shell under impact, such protection being achieved with respect to lateral blows and likewise blows in a vertical or oblique direction against the upper regions of the helmet shell.

Zji'ihdidtl Patented 2 U256 vessels, containers or walls, which is light in weight, dur' able, and characterized by the strength of fibrously-bondca plastic composition, while highly resistant to cracking or breaking and specifically free of any grain or lines of ready cleavage. A still further object is to provide such structure or structural material, peculiarly suited for helmet shells as well as for other uses, which may be integrally arranged to have different values of weight and strength at various selected localities.

Additional objects are to afford improved protective helmets of the character described, which are more effective for their intended purpose, which are light in weight, and which avoid uncomfortable or unsanitary effects such as have been encountered in prior types of helmets.

A particularly important object is to provide a helmet or other head covering having improved, adjustable headengaging structure such that a given embodiment of it will fit a Wide variety of shapes and sizes of head while nevertheless accomplishing one or more of the other objects of the invention, it being understood that the suspension means herein described are applicable to many kinds of headgear, including all types of helmets and hats designed to protect the wearer against blows, shock, projectiles, liquids, and effects of temperature and weather.

To these and other ends, the following description and annexed drawings show several useful embodiments of the invention, by way of examples to illustrate the novel' features and principles or improvement.

Referring to the drawings:

Fig. l is a longitudinal vertical section of the helmet, i. e. taken as if on a vertical plane intersecting the wear ers head from front to rear;

Fig. 2 is a transverse, substantially horizontal section on lines 2-2 of Fig. i;

Fig. 3 is a fragmentary view on line 3-3 of Fig. 1, with a portion of the structure broken away;

Fig. 4 is a transverse vertical section on line 4-4 of Fig. l;

Fig. 5 is a front elevation of the helmet; r

Fig. 6 is an enlarged view of a portion of the helmet shell body, with successive layers or parts of the constituent materials broken away to illustrate the method of lamination and assembly of the material;

Pig. 7 is a greatly enlarged sectional view, as if on line 7-7 of Fig. 6, showing the structure of the shell in crosssection;

Fig. 8 is a fragmentary elevational view of a portion of the right hand side of a helmet of the type shown in Figs. 1 through 5, illustrating a means for adjusting the lengths of the headband elements;

Fig. 9 illustrates another means of the headbands of 1 through 5;

Fig. 19 is a side view of a partly cut-away helmet shell containing a fully adjustable headband arrangement in which the headbands are adapted to encompass the entire perimeter of a head;

Fig. 11 is a lower, horizontal section on line illlll1 of Fig. 10, showing the headband arrangement;

Fig. 12 is a fragmentary view of a part of the headband arrangement of Figs. 10 and ii;

Fig. 13 is a fragmentary view of another part of the headband arrangement of Figs. 10 and 11;

of adjusting the lengths a helmet of the type shown in Figs.

Fig. 14 is a side view of a helmet with part of the shell cut away, the shell being such as to possess great resistance to deformation, and wherein headstraps are provided which are adapted to support the shell independently of the headbands;

Fig. is a front view of a helmet including the shell construction and the headstrap arrangement of Fig. 14; and

Fig. 16 illustrates means for adjusting the lengths of the headstraps of Figs. 14 and 15.

Referring first to Figs. 1 to 4, the illustrated example of a shock-resisting helmet includes a protective shell 20 having a generally hemispherical or other cup-like shape and made of strong, substantially rigid material. While a laminated, plate-like structure such as described hereinbelow ispeculiarly preferred for attainment of the desired results, especially for helmets to be worn by persons in airplanes or other vessels, vehicles or the like, it will be understood that a variety of materials may be used for the shell in many cases, e. g. fiber, plastic, metal or laminated or compound structures of various materials. The chief requirement is that the shell be substantially rigid and strong, so that under a heavy impact it does not fiex enough to strike the head of the wearer spaced within it and so that it has appropriate resistance to breakage, cracking or penetration by the striking object. It will also be understood that references to rigidity of the shell, and of plate-like material as hereinbelow described, do not exclude a minor degree of very stiff resilience,e. g. for very slight yielding under a heavy blow, if necessary to insure avoidance of cracking or breaking, but without enough actual displacement to impair the protective effect.

While the helmet may have various shapes and configurations in addition to the usual hemispherical-type part over the top half of the persons head, or alternatively may consist of said hemispherical-type part alone, the structure illustrated advantageously includes rigid depending flaps 21 at the sides, which (like adjacent side portions 22 of the upper helmet part) are somewhat bulged out. These flaps not only protect the side of the head but afford a covered space for earphones or like instruments customarily worn by the aviator. Similarly, the bottom edge of the helmet is lower at the rear 24a than at the front 24b, affording a skirt-like portion 25 to protect the base of the wearers skull. The entire lower edge of the helmet may be embedded in a protective bead or sleeve-like element 27 of rubber or similar resilient material.

Within the helmet and at a locality generally occupied by a single headband in other types of head-gear, the structure includes a pair of separate, substantially semicircular headband elements, namely a forward band or bandelement 30 and a rear band or band element 31, respectively adapted to pass, in conforming contact, around the front and rear of the wearers head which is indicated by dotted line 32 (Fig. 2). The forward headband element 30 has its respective ends secured to the shell at points spaced substantially to the rear of a central, transverse, vertical plane through the shell, while the rear headband element 31 has its ends similarly secured to the shell at points substantially forward of such plane. The ends of the front band element 3% are fastened to retainer plates 34, 35, riveted to the shell at 36, 37, while the rear headband element 31 has its ends secured to retainer plates 38, 39 riveted to the shell at 40, 41. The band elements thus cross at the sides, extending to the pairs of attachment points37, 41 and 36, 40, which are each substantially spaced in a horizontal direction, e. g. by several inches.

. The band elements 34), 31 may be made of suitable fabric tape, webbing, or like material, preferably having little or no elasticity. Their length is such that when curved around the forward or rear portion of the wearer's head (e. g. in each case about one-third of the circumference of the head) the tape cannot be advanced toward the adjacent front (or rear) inner surface of the shell beyond a predetermined spacing therefrom as indicated.

In addition to the anchorage at the sides, the band ele- A it ments are provided with spacing fabric supports, e. g. at localities between the sides, and the front and rear of the shell. Thus the forward band element 30 has a fabric support 43, again preferably of relatively inelastic tape, webbing or the like, disposed between the anchorage 36 and the forward face 44 of the band. As shown, the support 43 comprises a length of tape fastened at its ends to spaced localities 45, 46 along the band and centrally secured as by a rivet 47 to the helmet shell. A like fabric support 4-9 is provided at the other side of the band, i..e. between the anchorage 37 and the forward point 44,111: tape 49 being riveted to the shell at 50. At similar quarters of the rear band 31, corresponding fabric supports 52, 53 are provided riveted to the shell at 54, 55.

A further, preferred feature of the arrangement of the separate bands 3'9, 31 is that they are not essentially in the same plane but form a small angle with each other,

i. e. somewhat less than degrees, say at least 10 degrees to 20 degrees less. Furthermore, in relation to the head of thewearer, which though not shown is assumed to be in a normal upright position in Fig. l, the forward band preferably has a downward slope from the forehead to its points of anchorage, while the rear band has a downward slope from its anchorage localities to the back of ,the head of the wearer, i. e. so that the forward band rests against the wearers forehead while the tangent or abutting portion of the rear bandvcan be brought down to or toward the base of the wearers skull. By these relationships of the bands they seat firmly and comfortably around the head of the wearer, preventing inadvertent displacement of the helmet, either off the wearers head or by tipping at an angle in one direction or the other, yet at the same time the helmet is very easily put on or taken off.

It will now be seen that the structure and arrangement of the headbands affords a secure maintenance of the desired spacing of the shell from the head of the wearer at all points around the latter, e. g. particularly in alateral or near-lateral direction. More particularly, the arrangement is such that upon a blow against the shell in any direction, tending to move the shell, the head of the person is moved in the direction of the blow and there cannot be any substantial displacement of the shell relative to the head.

For example, assuming that the shell is struck at a locality in the vicinity of the rivet 50, as seen in Fig. 2, the entire shell tends to move as a unit, e. g. toward the upper right-hand corner of Fig. I2. Tension is correspondingly placed on the fabric support 52 and the end of the forward band 30 adjacent its anchorage 36. With the aid of the further supports and the conforming fit of the bands at the front and rear of the head, the wearers head is thus firmly moved, but without injury, .in the direction of the motion of the shell, maintaining the illustrated spacing between the locality (50) of theblow and the forward band 33. A blow in any other quarter of the helmet has a like effect with corresponding portions of the headbands and their supporting structure. Similafly a blow at the forward extremity 62 of the shell, tending to move the latter to the right as seen in Fig. 2, tensions both the ends of the forward band 30 adjacent their anchorages 36, 37, and will also tend to tension the supports 52 and 53. As a result the headband assembly, engaging the head of the wearer, is firmly displacedalong with the shell, similarly moving the wearers head and preventing any engagement of the shell with it. v

It will be noted that the bands, each lying in a curve of a generally paraboloid shape, or of a somewhat distorted parabola, are free of engagement with the sides 64, 65 of the wearers head, thus affording ample space for the ears and likewise for earphones or similar appliances, yet maintaining the shell in full clearance of'all of the latter at such localities. A particular feature of the arrangement is that the composite headband madeof separated parts is self-adjusting to fit a considerable variety avsasoe of shapes and sizes of head, e. g. whether of a long or short oval configuration or of difierent curvatures at front and rear. Furthermore, since there is no single band of fixed circumference, a number of head sizes may be fitted with a single assembly, for example, a range of hat sizes varying from 7 to 7%, or similar ranges for larger or smaller embodiments. The flexible nature of the bands, as well as their contact with only the forward and rear parts, thus not only permits self-adjustment in 'size and shape but also conformity with local irregularities of the head, for close and secure fit at all times. By anchoring the ends of the bands at positions beyond the center line, a maximum useful contact with the head is nevertheless afforded while still providing ample clearance for the ears and, if desired, instruments worn over them.

The structure also includes a longitudinal or fore-andaft head strap 79 extending from the central mid-point 44 of the forward headband 30, over the top of the wearers head, to the central mid-point 71 of the rear headband 31, being anchored to the bands at the stated localities. An attachment tab or strap '72 is secured to the strap 70, e. g. in tangent relation, at a locality '73 somewhat above (say at least an inch or so above) the point of attachment of the strap iii to the band 30, the tab 72 extending down to the forward edge 24-1) of the shell. A like tab or strap 74 is fastened at a similar locality '75 of the strap 7t), above the rear headband 31 and extends down to an anchorage at the rearmost edge 24a of the shell.

The described tangential attachment of the tabs 72, 74 to the head strap 71; thus in effect constitutes a single strap passing from the forward edge 24b of the shell over the wearers head to the rear, bottom edge 24a, while the end portions of the strap ;t"'merely serve to suspend the foremost and rearmost portions d4, 71 of the respective headbands, the composite strap assembly 727074 being of such length that it conforms to the upper surface of the wearers head and is spaced from the shell 20 at all points except the localities of attachment 24a, 24b. The support of the helmet in spaced relation above the head is thus dependent solely on the strap 70, with a cooperating transverse strap hilt. The headbands 30, 31 particularly at their forward and rear portions, are thus relieved of responsibility for maintaining the spaced relation of the shell at localities above their own planes; hence no downward slippage of the headbands or any angular displacement of them over the head can alter the upward spacing of the shell.

As mentioned, a like head strap 80 extends crosswise of the shell and over the head, being fastened at its midpoint 82 to a corresponding central locality of the band 70 and being anchored at its ends to appropriate retaining F plates 83, S4 fastened to the shell by rivets 85, 86 at central points of the sides, e. g. midway of the rivets 37, 41 and 36, as, but preferably somewhat below a line joining them. The band 86 conveniently passes outside of the headbands, i. e. between the end portions of the bands 39, 31 and the shell. It will thus be seen that the crossing straps 70, 550 form a secure seat for the supporting assembly on the head of the wearer, conforming to the upper part of the latter (say through an angle of at least about 150 degrees in a fore-and-aft direction, and nearly as much in the transverse direction) and being sufliciently flexible to fit a variety of shapes of skull crowns.

By virtue of the anchorages of these straps at least substantially in the plane of the bands 39, 31 and preferably below that general plane, the helmet shell Zi) is throughout its upper regions firmly maintained in substantially spaced relation from the wearers head. For example, a directly or singularly downward blow at any locality simply tends to put the lower ends of the straps 70, 89, i. e. the tab portion '12, 74- of the strap 70, as well as the immediate ends or" the strap 81), under tension without permitting any motion of the shell relative to the wearers head. To the extent that downward motion If desired, for further protection, particularly against dust or foreign particles and likewise for sound-deadening and general comfort and sanitation, a lining 83 of soft or flexible fabric may be provided throughout the interior of the assembly, e. g. arranged in generally hemispherical shape to fit within the straps 7d, 8t and being fastened along a forward section of the headband 3t) and a rearward section of the headband 31 as indicated. Finally, a

lower lining structure 9t) of flexible fabric or the like may be provided around the inside of the shell portions below the headbands, being secured at its lower edge 92 within the bead or sleeve 27 of the shell (Fig. 1) and extending upward to the lower edges of the headbands 3t 31, being fastened to the latter throughout a substantial part of the length of each, e. g. at least to points such as indicated at 93, 94 in Figs. 1 and 2.

The lower lining structure 95?, particularly in regions as indicated at 95, 96, below the head-engaging parts of the bands 30, 31 and extending to closely-adjacent portions of the shell edges 24b, 24a, constitutes an acoustical barrier, which serves to deaden vibration or resonance effects that may occur within the shell. For ventilation, the acoustical barrier portion of the lining, through the regions 95, 96 may be perforated at frequentintervals, e. g. as indicated by the holes as. 7

While the headbands 3b, 33. have been described as simple tapes or strap-like members, they may conveniently be constructed of a plurality of plies of fabric or webbing as shown, for instance at ms in Fig. l, e. g. in a single wide band folded along a central line as at 102 so as to form a narrow upwardly opening channel which may receive a sponge rubber or other resilient filler 194, the filler extending, for example, between the spaced points 93 of the forward headband 3i} and between the spaced points of the rear headband 3t (Fig. 2). This construction aifords a comfortable, soft and close-fitting 7 structure for the headbands. Indeed the portions of the bands just mentioned may have an inner ply Hi5 constituted by a portion of the lining structure 90 brought up, over the folded band portion 1%, as likewise shown. The upper lining 83 may similarly over-lap the headbands, in secure relation thereto, for example passing between the folded band element ice and the rubberfiller 104 at the forward side of the latter, as indicated at 1417.

Fig. 3 shows the manner in which the forward and rear ends of the headstrap it? are secured to the shell, or more particularly, the tab portions 72, 74 of such strap. As seen in Fig. 3, referring specifically to the forward end of the strap (the rear end being identical), the tab 72 is brought through a horizontal slot in the shell and then around the lower edge of the latter and fastened to its standing part, so as to form a closed loop 111. This loop may be further secured in place by a tied loop of cord 112 which also holds the forward end 92 of the lining structure 90. The entire assembly is then encased in the head or sleeve 27.

It will now be seen that the described arrangement of headbands and straps is peculiarly effective to mount the helmet on the head and to establish a definite and substantial spaced relation of say an inch or so, between the head and the helmet at all localities. A blow on the shell at any place or in any direction cannot force the shell against the head, but on the contrary will at most tend to displace the head while keeping the described spacing. Even in such case, the floating and flexible nature of the headbands and other parts absorbs any shock so that the wearer is fully protected. At the same time, the dual nature of the headbands provides effective and comfortable support with ample clearance for the ears and equipment there worn, while permitting a given structure to fit a variety of sizes and shapes of head. These functions of the dual bands are facilitated by their mutual angular disposition, a feature which also promotes security and comfort in the seating of the equipment on the head and facilitates rapidity of application and removal. The entire device is entirely sanitary and amply ventilated, and has no undesirable acoustic elfects. Having a minimum of parts and requiring no large or heavy cushions, the structure is extremely light in weight.

The helmet shell '26 itself, for example as shown also inFig. 5, is preferably constructed of an essentially rigid but very tough and strong material having a constitution such as illustrated in Figs. 6 and '7. This material is constructed of a plurality of sheets, originally highly flexible, which are superposed in layers and impregnated with an appropriate plastic composition or the like, as will now be described.

Thus in manufacturing the plate-like composition, a layer 130 of pre-formecl, felted material is first provided. On it is disposed a limited, fibrous, felted that 132 of high permeability overlaid by a fabric 134 of very open weave, the opposite side of the composite structure being completed by a further layer 56 of felted, fibrous material which may be similar to the layer 130. The sheets or mats 139, 136 areeach a relatively thin felted material consisting of irregularly laid fibers appropriately intermeshed but only very slightly bonded (by adhesive material or the like), so that such mat constitutes a thin, highly flexible and highly porous felt, the fibers being most advantageously glass fiber, or alternatively asbestos, mineral wool, or synthetic substances such as rayon or nylon, or'even cotton, wool or other natural fibers.

The layer or mass 132 consists of a slightly felted mat of relatively loose fibers which have been hailed up and which are essentially not bonded together, except by their mutual interlacing. The woven net or fabric 134, which may have a mesh as large as inch or so, is a reasonably strong but highly porous sheet, the fibrous composition of both the fluffed mass 132. and the woven fabric 134'being of suitable nature, such as the materials named above for the'mat layers 130, 136. As stated, the layers 130, 136 are pre-felted, rolled mats, i. e. thin felted sheets which have been passed between rolls but which are nevertheless highly porous.

Inpreparing the assembly to constitute an essentially monolithic sheet or plate-like material, the woven reinforcement 134 andfiufled layer 132 are assembled together, as on a suitable fiat surface or on a contoured form, and are impregnated with a bonding fluid, i. e. preferably to the point of at least as much as these materials will hold. The assembly of layers 132, 134 is then covered on opposite sides by the mats 13$, l3; indeed if desired, the materials 132, 134 may be laid on one or the other of the mats 130, 136 before the bonding fluid isapplied to the inside materials 132, 134.

After the second of the mats 130, 136 has been disposed in place, the entire assembly is subjected to considerablepressure, for example by holding it between congruent male and female dies or like surfaces which have the shape of the helmet shell, such dies being brought and maintained together with substantial pressure lhile the bonding fluid solidifies or dries or otherwise sets to at least a sufficient extent to maintain the integrity of the assembly when the dies are removed. Pressing the outer layers together against the impregnated central layers 132, 134 in this fashion not only causes the fiufiedfibers of the layers 132 to become intertwined with the fabric 134 (as apparent in Fig. 7), but also forces out any air that may be trapped in these layers, and finally causes the bonding fluid to flow into the outermost layers130, 136, filling the voids in the latter.

While the operation has been described as involving the assemblyof thewoven fabric 134 over the flu'ffed material 132, it-will'be understood that the flulfed ma terial may alternatively be placed over the woven'fabrib,

and 1134, but also the outer layers 1% and 136 so that single, unified or essentially monolithic structure is provided. After the pressing operation has been co'm pleted and the bonding fluid has dried or set to a solid state, the assembly becomes an essentially rigid but'remarkably strong, plate-like structure. A particular fea' ture of the arrangement is that unlike shell material s made by plastic impregnation of close-woven fabric bases, the complete structure of grain or other-predetermined lines of cracking or cleavage,

yet is fully as tough and durable by reason of the rein forcement of the fabric 134 as well as by the intermeshed nature of the other fibrous materials, particularly the fiulfed fibers 132 traversing the openings of the material The bonding medium' may alternatively'be applied after all layers have been assembled, although the insertion of such material at least prior to addition of the outermost or uppermost layer is believed desirable for maximum insurance against entrapment of air. The bonding medium employed may be any of variousplastic or like compositions, either of thermoplastic or thermosetting type, or of the type which can be liquefied bysolution in a volatile liquid. Low pressure molding compositions have been found especially suitable. For instance, excellent products have been obtained with polyester resins, compounded and molded in known ways suitable to yield tough. rigid (of for some purposes very slightly or rigidly resilient) bodies having good dimensional'stability. Examples .of these thermosetting substances are the so-called polyester Selectrons (made by Pittsburgh Plate Glass); thus a mixture of 49% each of polyester Selectr'ons 5003 and5208 with 2% of an organic peroxide material'such as Luperco ATC (made by Novadel-Agenc) has yielded satisfactory hard-crown helmet shells. Variations inhardness or flexibility (e. g. when the cheek or car flaps areto be more or less flexible than the crown) are obtainable .by suitable variation in proportions. Another kind of plastic substance especially useful for helmet shells of the impregnated fibrous-base type comprises phenolic compositions, for example various known'low pressure molding materials of such composition. As stated, the fibers of thevarious layers can be of various substances, glass fiber being at present preferred, but other natural or synthetic fibers being also useful, including asbestos, mineral wool, wood fibers as well as others mentioned above. The fibers for the severallayers may be allialilte or may be of mutually different substances, it now being understood that the nature of the bonding n'xedium as well as the fibers can be selected to suit the c rcumstances under which the ultimate structure is to give service.

While the composite material, thus composed of inter; bonded fiber layers permeated with a solidifiedplastic substance so as to constitute an essentially sIrloo'th-surfaced sheet, has been described as for constructionof the helmet shell 2", this type of sheet orplate-like material may be used for the manufacture of other devices, such as boxes, containers or the like orrnay be usecl'inpanels or other shapes as parts of objects to be assembled' The Figs. 5, 6 and 7 has no'liriear procedure and product are conveniently adapted for manufacture by a pre-rnold operation, e. g. as between dies mutually shaped to fit the configuration of the desired helmet shell or other structure. Alternatively, if the material is made for sheets or panels, the bonding and pressing operations may be effected by passing it between rolls or the like. It will now be seen that the resulting article, for example the helmet shell 2213', is rigid, tough and remarkably durable. Furthermore, it has no grain in any predetermined direction and consequently has no tendency to crack or split along predetermined thread lines or the like, as characterizes ordinary impregnated fabrics when struck by a sharp, heavy blow. The resistance to penetration on impact has been found to be very high, as likewise the resistance to chipping, cracking, appreciable bending or the like. In consequence, the complete assembly of helmet as shown in Figs. 1 to 5 inclusive, affords a peculiarly secure, protective device, guarding the head of the wearer against the effects of heavy blows, either by displacement of the helmet against the head or by any actual fracture or cracking of the helmet shell.

The thickness, weight and rigidity of the platelike composition can be varied by altering the number or the thickness of the layers or plies. For example, the open weave fabric 134, or some of the soft, flud'ed fibers of the mat 132, or both, can be omitted at the ear flaps 121 of the helmet so as to make these flaps more flexible in the finished state. Indeed for some types of helmet or the like, the woven fabric 134 may be omitted entirely.

Fig. 8 shows a means of adjusting the lengths of the headbands 3i) and 31 of the helmet illustrated in Figs. 1 through 5 and described above, so that the headbands can be made more readily comformable to varying head sizes. Two substantially parallel vertical slits 140 and 141 are cut in the shell 28 of the he.met at locations approximately corresponding to the points 36 and 44 where in Figs. 1 and 2 the forward band 30 and the rear band 31 are anchored, respectively, to the shell 2U.

Thus in Fig. 8 the end of the forward band 30 passes outward of the shell 2% through the slit 141 and then in a forward direction, while the end of the rear band 31 passes outward of the shell through the slit 140 and then rearwardly again, outside the shell. For this arrangernent the bands are made suitably longer than in Figs. 1 and 2.

A piece of fabric 142 is anchored to the outside of the shell 20 as by a rivet at 143. The fabric 142 may preferably be of the same material as are the bands and 31.

The fabric 142 serves to carry a pair of buckles 144 and 145, between the point 143 and the slits and 141, respectively. The ends of the bands 3% and 31 are adjustably held by their corresponding buckles, in a wellknown way.

Fig. 9 illustrates another means of permitting adjustment of the lengths of the headbands 3d and 31, eliminating the necessity of riveting any buckle structure to the shell of the helmet, as is required where an arrangement similar to that of Fig. 8 is employed. This construction is similar to that of Fig. 8 in that two slits and 151 are cut in the shell 29 of the helmet at similar locations of the shell 20.

A strip 152 of metallic, plastic or other suitable material (preferably of stiff resilience) is adapted to engage the slits 150 and 151 in a snap-fit arrangement by means of the curled ends 153 and 154- of the strip 152. The strip 152 is provided with a first vertical slit 155 near its middle, and with a second slit 155 between the slit 155 and its end 153, and also with a third slit 157 between the slit 155 and its end 154. A saw-tooth tongue 158 is attached in hinge like fashion to the buckle strip 152 at or near its curled end 153, and another saw-tooth tongue 159 is similarly attached to the strip 152 at or near its curled end 154.

The forward headband 30 passes outward of the helmet through the rearward slit 151, and the rear headband 31 it) passes outward of the helmet through the for'wafd slit 150.

To anchor the forward headband 3G, for example, to the buckle strip 152., the end of the band 30 is passed along the outer surface of the strip 152, and threaded through the central slit 155. It is then passed along the inner surface of the strip 152, threaded through the slit 157, and under the saw-tooth tongue 15?. The rear headband 31 is anchored in similar fashion to the strip 152. For this operation, performed when the helmet is off the head and the bands are slack, the buckle strip 152 is conveniently removed from the slits 150, 151, so as to permit free access to its various parts.

Thus it will be seen that when'the headbands 30 and 31 are adjusted to the proper length for a given head, and have further been threaded as aforesaid through the slits 156 51, 155, 156 and 157 and under the saw-tooth tongues T153 and 159', then the buckle strip 152 may be snapped into place.

When there is no head in'the helmet, and hence the headbands 3i and 31. are untensioned, no inadvertent'alteration of the completed adjustment is possible. This is due to the fact that the portion of the headband 30 between the slit 155 and the slit 1S7, indicated at 169, is clamped against the outer surface of the shell 26 by the buckle strip 152. Similarly, the portion of the rear headband 31 between the slit 155 and the slit 157, indicated at 161, is clamped between the strip 7152 and the outer surface of the shell 26.

When the headbands 30 and 371 are tensioned due to the presence of a head within the helmet, that portion of the headband 3b which passes over the tongue 1S9 forces the teeth of that tongue toward the shell 2% of the helmet, embedding the teeth of the tongue into the fabric of the headband 3i) and preventing any alteration of its adjustment.

Similarly, the teeth of the tongue 158 become embedded in the fabric of the rear headband 31, preventing any alteration of its adjustment.

Figs. 10 and 11 detail an example of a fully adjustable headband arrangement in which the headband elements encompass the entire perimeter of a head, essentially regardless of contour irregularities. Fig. It) shows the side and Fig. 11 the plan of such headband arrangement. The headband elements are secured to the shell of the helmet without necessitating the use of rivets or similar means.

The arrangement is shown in connection with a helmet shell (to be described) which is an improvement upon the shell structure of the helmet shown in Figs. 1 through 5. In Figs. 10 and 11, a forwardly attached back headband or headband element 171 of suitable flexible fabric is closed, for example, by stitching at 172 to form a closed loop. A portion of the band 171 lies outside the shell 170, passing through two slits 173 provided in the forward part of the shell 170 for that purpose. The slits 173 are preferably a distance apart considerably less than the width of the head upon which the helmet is to be worn,

i. e. less than the maximum transverse distance (indicated,

at 173a) across the headband assembly for the smallest head to be fitted.

The major portion of the band 171 lies within the shell 17! in a plane which is slightly inclined, being lower in relation to a normal upright inserted head toward the rear of the helmet than toward the front thereof.

A rearwardly attached front headband or headband element 174 of suitable fabric is provided, and is in general similar to the forwardly supported headband 171. It is preferably coplanar with the band 171. A portion of the band 174 lies outside the shell 170, passing through two slits 175 provided in the rear part of the shell for that purpose. Like the slits 173, the slits 175 are preferably a distance apart considerably less than the width 173a of the head upon which the helmet is to. be worn.

The ends of the rearwardly attached headband 174 are 11 adjustably'secured together outside theshell 170 between the slits 175 by a suitable buckle 176.

The central portions of the band 174, at177, are of flat tubular construction, and are provided with two suitable holes 178 outwardly of the band 17 4 at the forward ends of the tubular central portions 177, and with two suitable holes 179 inwardly of the band 174 at the rearward ends of the tubular central portions 177.

The forwardly attached headband 171 passes through the holes 178 and extends within the central tubular portions 177 of the rearwardly attached headband 174 in freely slidable relation therewith, and then passes through the holes 179. This portion of the headband 171 is shown by the dash lines at 180 (Fig. 11). Thus the forward portion of the perimeter of the head will be engaged by the corresponding portion of the headband 174, the rearward portion of the perimeter of the head will be engaged by the corresponding portion of headband 171, and the side portions of the perimeter of the head will be engaged by the central tubular portions 177 of the headband 174, with the central portions 186 of the headband 171 therein. A convenient mode of construction is to make the band 174 of tubular fabric throughout its length (and indeed also the band 171); in use it then remains flattened both at the front and rear, but is spread suiticiently between the holes 178, 179 on each side to admit the other band 171 in the described telescoping relation. It will be noted that, considering the band 174 in its flattened state, the holes 178, 179 are located respectively on opposite faces, so that the band 171 extends (on each side) from a forward region outside the band 174 into the aperture 178, and then leaves the aperture 179 on the inner side of the band 174.

The fact that the slits 173 and the slits 175-are a distance apart considerably less than the width of the head upon which the helmet is to be worn means that the helmet shell 170 is positively held in constant spaced relation to the head in all lateral directions. That is to say, the headband assembly affords, in use as shown, the configuration of a central, head-engaging ellipse or other oval shape encompassed in an elongated, similar shape having considerable portions of opposite sides in common. Since the outer, supporting parts of the bands extend tangentially to the central oval along lines which slope substantially (in plan) toward the major axis, the head is positively held, in spaced relation within the helmet at all times. Furthermore, the effect of a blow, say in any lateral or even downwardly angular direction on the exterior of the helmet shell, is to maintain the spacing by tensioning certain of the members in the same direction in which they are drawn or tensioned by their adjiustably fitted relation to the head. The band thus tends to be drawn more snugly about the head (againstdislocation) atthe time of a blow, while the supporting parts function as described, to keep the shell spaced away. Finally, since the original adjustment of the telescoping bands to fit a given head necessarily requires that the outer parts of the bands be under tension when the helmet is worn (and properly fitted), there is thus always a positive assurance that such parts are tensioned for their spacing function, when needed. I

The central portions 177 may, if desired, be provided with a plurality of sway braces 181 of'flexible fabric extending outwardly from the central portions 177 and fastened to theshell as by rivets 182 (Fig. 11). The swaybraces 181 serve chiefly to prevent the helmet from swaying about a tront-to-back axis through the head or a wearer. Although the supporting parts of the bands 171, 174' constitute the primary lateral spacing means for the head-encircling structure, and ind'eedare in most instances adequate of themselves for that purpose (as likewise, in some cases, are the anchored end portions of bands 30, 31 in Fig. 2), the braces 131' are also adapted to cooperateas tension members to-the same end, i. e.

. l2 in acting like the outer loops of the bands 171, 174o'r the, supports 43, 49, 52 and 53 of Fig. '2, to move'the wearers head in the same direction as the helmet and thus in spaced relation inside it, when it is struck.

Fig. 12 shows a portion of the headband construction described above in connection with Figs. 10 and ll but in more detail. Fig. 12 includes the forward portion of the rearwardly fastened front headband 174, and a portion of its tubular central portion 177, which is cut away to show the central portion of the forward headband 171. Also shown is one of the sway braces 181.

Fig. 13 shows means similar to that employed in con: nection in the construction of Figs. 1 through 5 for preventing upward movement of the headbands 171 and 174-, for example, as a user is putting the helmet on. This purpose and at least to some extent the like purpose of impeding similar mutual displacement between the shell and the headbands at other times, are accomplished by the means of Fig. 13, which serves toanchor the headband to the shell in a vertical sense. The illustrated means comprises a strip of flexible fabric 183,.one end of which passes through a slit 185. in the shell of the helmet at the front and is there fastened to the shell as by a rivet 186. The slit 185 and rivet 186 are conveniently disposed below theplane of the headband assembly, so that the strip 183 extends upward to the forwardmost part of the band 174 where it is attached, as by stitching 184. More than one such strip can be provided if desired. A similar strip or stripsmay be advantageously, and indeed is preferably provided at the rear portion of the forwardly supported headband 171, as indicated at 1830.

It should be appreciated that the headband suspension of Figs. 10 through 13 will be useful in connection with the manufacture of various kinds of headgear, especially those involving a more or less rigid outer shell.

it will be seen that a helmet including the features of Figs. 10 through 13 provides a fully adjustable headband construction in which the headbands are adapted completely to encircle the head regardless ofcontour irregularities thereof. As indicated, the construction may be such that no rivets are required to fasten the headbands to the shell of the helmet. The adjustment is controlled by the buckle 176 which may conveniently be at the rear as illustrated. As a matter-of fact, two buckles, one as shown and the other at the front of the helmet (for the band 171) can be used, if desired; or only one buckle at the front of the helmet. can be provided. At the same time, a fixed spaced relation between an inserted head and the shell of the helmet will be positively maintained.

A particular advantage is the relatively wide range of adjustability, for example in that a single devicemay bermade to fit any one of the normal range of adult head sizes; or even where such range of utility for a single shell is not wanted, there is great advantage in satisfying all head sizes with not more than two or three basic sizes of helmet and headband assembly. In all cases, the slits 173 and likewise the slits 175 are preferably spaced by distances substantially smaller than the minimum head size to be accommodated in the given device; and as indicated, all of the advantages ofshell spacing, ruggedness, and perfection of fit are obtained throughout the range of adjustment,,together with a highly shock-proof, non-slipping character of the assembly. Furthermore, such an adjustable construction permits the helmet to be Worn comfortably-and with proper fit, for example where the head is first covered with an inner, flexible cap or helmet (for warmth), or where the head may be bandaged in one way or another, or indeed in any situation in whichra headband of greater than normal diameter, or of unusual shape, may be required.

Figs. 14 and 15 show, respectively, a side view and a front view of a helmet with part of the shell cut away and wherein means are provided for supporting the shell of the helmet independently of the headbands. This is accomplished by means of headstraps 187 having their upper ends secured to a cap 188, which may be preferably of fabric, and their lower ends permanently anchored to the shell of the helmet as by rivets 189, e. g. at circtunferentially distributed localities in the plane of the headband assembly, which though not shown in Figs. 14 and 15, is indicated by the band-retaining slits 173 and 175.

In Figs. 14 and 15 the headstrap assembly is rotated approximately 45 degrees from that of Figs. 1 through 5. This arrangement has certain advantages, for example in providing better clearance for earphones than is afforded by the arrangement of Figs. 1 through 4. In essential respects, however, the structure of Figs. 14 and 15 serves the same function as the headstraps of Figs. 1 to 4, namely to seat the assembly in firm and conforming relation over the crown of the wearers head,

relieving the headbands of the weight of the shell and maintaining substantial spacing above the head, despite downward blows or the like on the shell.

inasmuch as the distance from the crown to the ears of a head varies from one individual to another, and to permit the use of only a relatively few standard sizes of helmet shells (or indeed often, of only one size of shell for a normal range of head dimensions), the headstraps of Figs. 14 and 15 may be made adjustable, as shown in 16. Thus a portion of a helmet shell 1% is shown, together with a portion of a headband 17 l-171 and a portion of a headstrap 192. The headstrap, instead of being permanently anchored to the shell 1% as by the rivets shown in Figs. 14 and 15, is adjustably attached thereto by a buckle 193. Thus each strap may be brought up through a horizontal slit 193a in the shell and held by the tongue 19317 of the buckle device 193 secured on the outside of the shell.

It will be understood that helmets such as shown in Figs. 14 to 16 are provided with suitable headband structure cooperating with the headstrap assembly to keep the shell in spaced protective relation to the head, such headband structure being very preferably of the type shown in Figs. to 13. As shown in Fig. 16, the headstraps 192 (or 137) can conveniently be fastened to the shell at the same circumferential localities as the sway braces 181, the illustrated strap 192 being apertured at 192a to accommodate the brace 1811.

Figs. 14 and also show a modified construction of the shell of the helmet. The result of such modified construction is that a helmet shell having even greater resistance to deformation is achieved. Thus when such a shell, of a given weight, is struck a severe blow, it will have even less, and indeed usually no tendency to become flattened in the vicinity of the blow, nor will the shell become buckled in. Fig. 10 also shows the same shell construction.

In this modified construction, the shell is provided with a plurality of substantially vertical ribs 194 (four are illustrated) which have a hollow or channel-like shape in cross section and which protrude outwardly of the shell and are preferably of considerable width relative to the thickness of the shell, as shown. For example, if the shell is made of fibrous material impregnated with low pressure plastic (i. e. made by molding the structure with one or another of various suitable plastics at low pressure) and the ribs are made too narrow, a phenomenon which may be termed bleeding is likely to occur. That is, the concave or inside portion of a narrow rib tends to become filled with plastic, causing the rib to flatten out. Such flow of excess plastic into areas of non-uniform pressure represented by narrow rib channels produces excess weight along these regions of the finished, solidified shell, with consequent non-uniformity of strength in the shell and even a tendency to cracking or breaking adjacent the linear boundaries of the ribs. With the i i wide, channel-like ribs, preferably having an inside transverse dimension at least several times the shell thickness, such difiiculties are obviated and the wall of the article has essentially the same strength throughout.

The ribs 194 meet each other at or near the top of the shell where they intersect in a uniform cross-like configuration, with their channels merging in communication with each other. The lower ends of the ribs 194- are terminated by a substantially horizontal trough-like or reversely channeled portion 195 which extends all the way around the helmet from the base of the skull area to the forehead area, above the ear flap area. The inwardly recessed channel or trough-like portion 195 is, like the ribs 194, preferably considerably wider than the thickness of the shell, and for the same reasons.

It should be noted that, in addition to providing a reinforcement for the helmet shell, the trough-like portion 195 may cooperate with structure such as shown in Figs. 14 and 15 to impart or enhance a hinge-like flexibility at the upper parts of the ear flap areas 196, 197 of the shell, permitting some outward bending of the earflaps and making it easier for a wearer to put the helmet on past his ears, and especially over headphones or the like. That is to say, the substantially horizontal, peripheral channel 195 (which may be outwardly concave as shown in Figs. 14-15 or may be an outwardly convex beading, and may be applied to the structure of Figs. 1-5) provides a strong, essentially rigid, annular reinforcement for optimum protection of the skull against side blows, while also providing a solid hinge fulcrum or axis (e. g. in Figs. 14-15, below the locality where the crown ribs 1% at the side merge into the channeled portion 195), against which the ear-flap portions 3%, 197 or the like may be made to flex, preferably with the cooperative effect of more flexible shell material embodied in the flaps or suitable portions of them.

As indicated above, the headband and other harness or head-engaging structures herein described are applicable to headgear generally, i. e. including many types of hats for a wide variety of purposes, as well as the illustrated protective helments that are primarily designed for military and like uses.

It is to be understood that the invention is not limited to the specific embodiments hereinabove described but may be carried out in other forms without departure from its spirit.

Having thus described our invention, we claim:

1. A protective helmet comprising an outer shell, forward and rear substantially inelastic headband elements each having a generally arcuate central portion adapted to engage conformably a wearers head and end portions extending tangentially from said central portion to the shell, means attaching said end portions to the shell, each central portion being dimensioned tobe spaced substantially uniformly inwardly of the shell, and tensionable but normally unstressed spacing means fixed to and extending between the shell and each central portion and cooperating with said end portions to maintain said spacing substantially constant.

2. The invention set forth in claim 1 wherein, in relation to an enclosed head in normal upright position, the central portion of the forward headband element is higher than its points of fastening and the central portion of the rear headband element is lower than its points of fastening.

3. The invention set forth in claim 1 wherein the plane defined by the rear headband element makes an angle of less than degrees with the plane defined by the forward headband element.

4. The invention set forth in claim 1 wherein, in relation to an enclosed head in normal upright position, the central portion of the forward headband element is higher than its points of fastening, the central portion of the rear headband is lower than its points of fastening, and the plane defined by the rear headband element is more 15 nearly horizontal than the plane defined by the forward headband element.

5. A helmet as described in claim 1, wherein the ends of the forward headband element are attached to the shell at localities spaced rearwardly of a transverse medial plane through the helmet and the ends of the rear headband element are attached to the shell at points spaced forwardly of said medial plane, said headband elements being held by the spacing means at an angle of less than 180 degrees to each other but maintaining the head-conforming portions of said headband elements in substantially a single plane.

6. A protective helmet as described in claim 1, which includes an acoustic barrier of flexible material extending between each headband element and the shell at a lower region of the latter throughout at least the portion of each headband element which is adapted to engage the corresponding head portion conformably, said acoustic barrier being apertured for ventilation of the space between the head and the shell.

7. A headgear comprising an outer shell, substantially inelastic forward and rear headband elements, each having an arcuate portion adapted to engage conformably a corresponding portion of a head, said portions cooperating to form a head-encircling band, connecting means including other portions of said band elements fixed to and extending between said arcuate portions of the forward and rear headband elements respectively and the rear and forward portions of said shell, said connecting means maintaining said head-encircling band in substantially constant spaced relation to the shell and substantially unstressed when not engaging a head, said band being stressed uniformly in tension upon conforming engagement thereof with a wearers head.

8. A headgear as defined in claim 7 including means for preventin said headband elements from travelling upward as the headgear is put on.

9. A headgear as defined in claim 7 including headstrap means adapted to extend over the inserted head, said hcadstrap means being secured to oppositely spaced lower localities of the shell and being spaced inwardly of the shell above the points of said attachment.

10. The invention set forth in claim 9, which includes flexible means extending between the headband elements and localities of the shell below the headbandelements, to prevent said headband elements from travelling upward as said helmet is put on.

11. A headgear as defined in claim 7, including headstrap means adapted to extend over the inserted head,

said headstrap means being attached to lower localities of the shell and being spaced inwardly of the shell above the points of said attachment, spacing means secured between the shell and said headband elements to cooperate therewith in preventing lateral sway of said helmet upon the head of a wearer and means including straps secured between said headband elements and a locality of the shell downward of said headband elements for preventing said headband elements from travelling upward as said helmet is put on.

12. A headgear comprising a shell and headband means therein providing an adjustable head-encircling band con figuration spaced laterally within the shell, said means including two sets of telescoping band portions forming respectively opposite sides of the said configuration, band portions extending between the ends of said first band portions and connected to the latter and forming other opposite sides of said configuration, and band means extending from the ends of each of the sets of telescoping portions to the shell and supported by the shell at localities spaced from but near the crosswise baud portions.

13. A headgear comprising a shell and headband means spaced therein, said headband means including a band loop extending from one region of the shell to a locality near but spaced from an opposite region, a band loop extending from said opposite region to a locality near butspaced from the first region, said band loops overlapping each other to define a head-encircling space, and side parts of the overlapping portion of each loop being connected in supporting relation respectively to the corresponding side parts of the other loop.

14. The invention set forth in claim 13 wherein the said regions are arranged respectively at the front and rear ends of the shell relative to the head to be inserted therein, each loop having a pair of end parts supported by the shell at localities spaced laterally in the corresponding region, said localities being spaced, in each region, by a distance substantially less than the width of a head which the defined head-encircling space is adapted to fit, the side parts of one loop being longitudinally slidable relative to the side parts of the other loop, and at least one of the loops comprising adjustable means for taking up and letting out said loop, to adjust the size of the defined head-encircling space.

15. The invention set forth in claim 13 wherein at each side of the defined head-encircling space, the side part of one loop comprises a tubular portion extending along it and disposed in slidable, telescoping relation around the associated side part of the other loop, for the aforesaid supporting connection of the side parts.

16. A protective helmet comprising an outer shell and a harness assembly for holding an inserted head, said harness assembly including rear and forward headband elements secured to the forward and rear portions of the shell, respectively, and each forming a loop spaced inwardly of the shell, each said loop being adapted to engage conformably a corresponding portion of the head, said loops together being adapted to engage the entire periphery of the head from the forehead to the base of the skull, said headband elements being adapted to hold the head in substantially constant spaced relation to the shell upon the application of sudden force laterally against the shell.

17. The invention set forth in claim 16 wherein tensionable spacing means are secured between the shell and each headband element to cooperate in maintaining said spaced relation constant and to prevent the shell from swaying relative to the head about a vertical plane centrally intersecting the head from front to back.

18. A protective helmet comprising: an outer shell having a forward portion, a rear portion, a first pair of spaced apertures in said forward portion and a second pair of spaced apertures in said rear portion; and a harness assembly for holding an inserted head and including first and second elliptical-like, substantially coplanar headband elements, said first and second headband elements passing through said first and second pairs of apertures, respective- 13/, one of said headband elements having means by which the other of said headband elements can pass therethrough; and means for adjusting said harness so that it can accommodate varying head sizes; said headband elements being adapted to engage conformably the entire periphery of an inserted head.

19. The invention set forth in claim 18 wherein said harness assembly also includes a plurality of headstraps each having an upper end and a lower end, means holding said upper ends near each other within and near the top of the shell, and means securing said lower ends to said shell, each said hcadstrap being adapted to engage conformably a corresponding portion of the head.

20. The invention set forth in claim 18 wherein said harness assembly also includes a plurality of headstraps each having an upper end and a lower end, means holding said upper ends near each other within and near the top of said sheil, means securing said lower ends to said shell, and means for adjusting the lengths of said headstraps, each said headstrap being adapted to engage conformably a corresponding portion of the head.

21. A protective helmet comprising an outer shell and a harness assembly for holding an inserted head in substantially constant spaced relation with said shell, said arranges harness assembly including first and second headband elements, said first and second headband elements passing through a first pair ofapertures in the forward portion of the shell and a second pair of apertures in the .rear portion of said shell, respectively, each said headband element forming an elliptical-like loop the major portion of which is inside the shell and the remainder of which is outside the shell between the apertures of the corresponding pair of apertures, one of said headband elements having tubular portions along the sides thereof, the other of said headband elements passing through said tubular portions, and means including a buckle for adjusting said harness to accommodate varying head sizes, said head band elements being adapted to engage the entire periphery of an inserted head.

22. The invention set forth in claim 21 wherein the apertures of each said pair of "apertures are a distance apart substantially less than the maximum width of an inserted head.

23. A protective helmet comprising a rigid outer shell, headband means within the shell and spaced laterally therefrom and substantially concentric therewith, connecting means extending between and attached to spaced points on said headband means and spaced points on said shell, said connecting means being effective to maintain said headband means laterally spaced from the helmet, and headstrap means adapted to extend over the head of a wearer, said headstrap means having its ends free of said headband means and being attached at its ends to said shell at a level below said connecting means attaching points, said headstrap means being formed of flexible, substantially inelastic material and dimensioned to engage conformably the crown of the wearers head and effective when the shell is placed on a wearers .head to support the shell and to transmit to the head downwardly directed external forces, so that such forces and the weight of said shell are ineflective to displace the headband means with respect to the head.

24. A protective helmet comprising an outer shell, a forward substantially inelastic headband element having a central substantially semi-circular head-engaging portion and end portions extending tangentially from said central portion to the sides of the shell at points spaced substantially to the rear of a central, transverse vertical plane through the shell, a rear substantially inelastic headband element having a central substantially semi-circular headengaging portion and end portions extending tangentially from said central portion to the side of the shell at points spaced substantially forward of said plane, means attaching said end portions to the shell, and spacing means fixed to and extending between the shell and each headband element and cooperating with said end portions to maintain said head-engaging portions spaced uniformly inwardly of the shell, even upon the application of sudden lateral force against the shell.

25. A protective helmet comprising an outer shell, forward and rear substantially inelastic headband elements, each having a generally arcuate central portion adapted to engage conformably a wearers head and end portions extending tangentially from said central portion to the shell, means attaching said end portions to the shell near the middle thereof, said forward and rear elements having their ends attached to the shell respectively to the rear and to the front of said middle, said end portions extending away from the wearers head toward the shell to provide space between the shell and the head in the region of the ears.

26. A protective helmet comprising an outer shell, a forward headband element secured at its ends to the sides of the shell at points to the rear of a central transverse vertical plane through the shell and having an arcuate central portion adapted to engage conformably a forward portion of a wearers head and end portions projecting tangentially from said central portion to the shell, a rear headband element secured at its ends to the sides of the shell at points forward of said plane and having an arcuate central portion adapted to engage conformably a rear portion of the head and end portions projecting tangentially from the central portion to the shell, and a plurality of flexible means fixed to and extending between each central portion and the shell, said end portions and each of said flexible means being substantially inelastic longitudinally and thereby effective, when under tension, to prevent displacernent of the adjacent portion of its headband element further from the shell than its length permits.

27. A protective helmet as defined in claim 26, including a headstrap having one end fastened to a -forwardmost locality of the shell below the forward headband element and its other end fastened to a rearmost locality of the shell below the'rear headband element, said headstrap being adapted to extend over the head of a wearer and including means flexibly extending therefrom respectively at each of two localities substantially above the respective headband elements and between the ends of the strap and the uppermost region thereof, to the forwardmost and rearmost portions of the headband elements, to suspend the said last-mentioned portions of the headband elements from theheadstrap, and a transverse headstrap having its ends fastened to the sides of the shell at localities at least as low as the fastening points of the headband elements, said ends of the transverse headstrap being free of said headband elements, said second headstrap crossing the first headstrap at an uppermost region of the head and being there secured to the first headstrap, and each of said 'headstraps being dimens'ioned to engage conformably the crown of the head in spaced relation 'to the shell and adapted to project tangentially from the head toward the fastened ends of the strapf- Y 28. A protective helmet comprising an outer shell, forward and rear substantially inelastic headband elements each having a generally arcuate central portion adapted to engage conformably a wearers head and end portions extending tangentially from said central portion to the shell, means attaching said end portions to the shell, each central portion being dimensioned to be spaced uniformly inwardly of the shell, an acoustical barrier of flexible material extending from the headband elements to the shell, and tensionable but normally unstressed spacing means fixed to and extending between the shell and each central portion and cooperating with said end portions to maintain said spacing substantially constant.

29. A headgear comprising a rigid outer shell having internal dimensions large enough to receive the head of a wearer with substantial clearance about the entire periphery of the head and ShelL'headband means including portions adapted to engage a wearers head in conforming contact, said portions being flexible and substantially inelastic, and means supporting said portions in inwardly spaced, substantially uniformly concentric relation to said shell and maintaining said portions substantially unstressed when not engaging a head, said portions being stressed substantially uniformly in tension upon conforming engagement with a wearers head, said supporting means comprising a plurality of flexible, substantially inelastic straps within and spaced circumferentially around the shell, each strap being fixed at points longitudinally spaced along the strap to the shell and to one of said head-engaging portions, so that an external inwardly directed force applied to one side of the shell is transmitted through the rigid shell to the straps attached to the opposite side of said shell, said last-mentioned straps being stressed in tension by said force, said stressed straps being thereupon effective to pull said headband means away from said one side and toward said opposite side, so that engagement of the shell with the head-engaging portions by said external force is elfectively prevented.

30. A headgear comprising a shell having internal diportions to the shell, and generally radially extending in- H elastic fabric strap means connecting said arcuate central portions to the shell, said strap means, said end portions and said attaching means cooperating to hold the entire length of said central portion substantially uniformly spaced from the shell and to maintain said headband element substantially unstressed when said arcuate central portion is not engaging a head, said headband element being stressed uniformly in tension upon conforming engagement of said central portion with a wearers head.

31. A headgear as defined in claim 30, in which the means attaching one of said end portions to the shell comprises adjusting means for changing the length of said headband element.

32. A headgear comprising a shell having internal dimensions large enough to receive the head of a wearer with substantial clearance about the entire periphery of the head and shell, and headband means for supporting the shell substantially centered on the wearers head, said headband means including a pair of flexible, substantially inelastic headband elements having generally arcuate central portions adapted to engage a wearers head in conforming contact, said central portions being complementary and located on opposite sides of a central, vertical plane through the shell, and end portions extending tangentially from said central portions to the shell, respectively on the opposite sides of said central plane from said-central portions, means attaching said end portions 'to the shell, an'd'generally radially extending inelastic fabric strap means connecting said arcuate central porti'ons to the shell, said. strap means, said end portions and said attaching means cooperating to hold the entire length of said'centr'al portions substantially uniformly spaced from the shell and to maintain said headband elements substantially unstressed when said arcuate central portions are not engaging a head, said headband elements being stressed uniformly in tension upon conforming engagement of said central portions with a wearers head.

33. A headgear as defined in claim 32, including means for adjusting the length of each headband element independently of the other, to adjust either the head size of the head-contacting portion of the headband means or the positional relation of said head-contacting portion with respect tothe front and rear of the shell.

References Cited in the file of this patent UNITED 'STATES PATENTS 1,646,272 Bates Oct. 18, 1927 1,938,660 Howard Dec. 12, 1933 2,123,275 Dym July 12, 1938 2,250,275" Riddell July 22, 1941 2,312,227 Yant Feb. 23, 1943 2,416,529 Lewis Feb. 25, 1947 2,420,937 'Dauster May 20, 1947 2,423,076 Daly July 1, 1947 2,428,654 9 Collins ......2 Oct. 7, 1947 2,432,164 -Kerr Dec. 9, I947 2,451,483 Goldsmith Oct. 19, 1948 2,573,250 Daly Oct. 30, 1951 2,585,937 Johnson et al. Feb. 19, 1952 2,629,095 Kleinman Feb. 24, 1953 

